Currently in the United States there are tens of millions of parenteral medications dispensed each year. Because of the sheer numbers and the repetitious nature of giving parenteral medication, errors in dosages unavoidably occur. Dosage errors result in complications, as well as deaths. Additionally, the number of people who self-administer parenteral medications has greatly increased in the past few years.
Devices have been developed to aid in the filling of and injection by syringes. U.S. Pat. No. 3,965,945 to Ross, issued June 29, 1976 discloses a preadjustable device to which a medicant syringe may be attached for the filling of the syringe with medicant. The device includes an over fill control to allow for a slight overfill of the syringe and the subsequent expelling of the overfilled medicant and entrapped air. The device includes a means for holding a syringe and a threaded shaft actuator in the form of a screw. The device includes no means to assist in the reading of the analogue indications on the syringe. That is, there are no means provided to assist the user in visualizing the amount of medicant drawn into the syringe barrel. This is a considerable problem with patients who self-administer drugs because such patients, such as diabetics, have poor eyesight.
The U.S. Pat. No. 4,261,358 to Vargas et al, issued Apr. 14, 1981 discloses an automatic syringe plunger. This device does not include any means for assisting the user in determining the amount of medicant drawn into the syringe.
The aforementioned patents are examples of prior art automatic syringe plungers, all of which having the problem of not assisting the user in visualizing the amount of medicant drawn into the syringe. The present invention addresses the aforementioned problem by providing a device for automatically dispensing parenteral medications using digital rather than analog systems to indicate clearly to the patient the amount of medicant drawn into the barrel of the syringe.